Allen-Bradley 1747OC-EEEAA SLC 500 Open Controller CPU

Allen-Bradley 1747OC-EEEAA is the SLC 500 Open Controller CPU module—a PC-based controller designed to run your application alongside AB's 1746 I/O in SLC 500 systems. The architecture comprises two CPUs, a SCANNER that handles the 1746 Local I/O bus and a CONTROLLER that executes your program, linked by a shared dual-port memory bridge that forms an 8K-byte partition between the two processors. The CONTROLLER employs a PC-class CPU (historically a 266 MHz Pentium-class or 5x86-class processor) and connects to the backplane via PCI (1747-OCF) or ISA (1747-OCE) bus interfaces, depending on the exact module revision. This Open Controller design enables PC-programming capabilities within a modular AB control system and leverages BIOS and OS-level software to load and run applications on the PCI/ISA bus alongside traditional 1746 I/O.